Over the ensuing months, Kyle underwent multiple surgeries to repair muscle damage to his leg and graft skin over his injuries. The operations were followed by physical therapy to restore function to his left knee and ankle.

And while Kyle has fully recovered from the accident, according to Morgan, the family's lawyer, the boy will need a $30,000 surgery later in life to remove scar tissue. The family has racked up more than $60,000 in medical bills so far, according to Morgan.

An investigation by the California Division of Occupational Safety and Health found that the Xcelerator accident could have been prevented with proper maintenance, casting blame on both the theme park and the ride manufacturer, Switzerland-based Intamin.

The report said the snapped cable exhibited "gross amounts of fatigue" and found the force of the accident sheared off 18 of the 20 magnets on the bottom of the coaster cars used for launching and braking.

The state's Xcelerator investigation also looked at a similar accident involving an Intamin coaster that occurred in 2004 at Knott's sister park, Cedar Point in Ohio, when metal debris from a launch cable struck four riders on the 420-foot-tall Top Thrill Dragster.

Knott's reopened Xcelerator more than a year ago after making modifications required by the state report, theme park officials said.